Aeration system and device for shoes

ABSTRACT

The present invention concerns an aeration system for shoes comprising an aeration device, specifically pumping means like a bellows pump, which constitutes a further object of the invention. 
     More specifically, the present invention concerns an aeration system for shoes, comprising a hollow sole ( 1 ) having an aeration device in fluid communication both with the inside of the shoe and with the outside, at least one first and a second cavity ( 2, 3 ) being formed inside said hollow sole ( 1 ), pumping means ( 9 ) being housed in said at least one first cavity ( 2 ), wherein said pumping means ( 9 ) comprise a shell ( 10 ) and a distribution nozzle ( 11 ), a flexible core ( 12 ) being housed inside said shell ( 10 ), and a pad ( 18 ) is housed in said second cavity ( 3 ).

FIELD OF THE INVENTION

The present invention concerns an aeration system for shoes comprisingan aeration device, specifically pumping means like a bellows pump,which constitutes a further object of the invention.

BACKGROUND ART

Both hygienic and medical reasons dictate the importance of keeping thefoot dry and well aerated. Good aeration, as well as dissipating badsmells, promotes the evaporation of the sweat that inevitably forms,above all in hot weather or during physical effort. The sole of the footis indeed one of the parts of the human body where the sweat glands aremost concentrated. The problem of excessive sweating has become moreserious with the appearance of the rubber sole replacing the leathersole. The rubber sole, indeed, whilst being advantageous in terms ofboth heat insulation and water-proofing of the foot and the possibilityof modelling the tread to make it grip better on the ground, isnevertheless impermeable to air and does not allow sweat to transpire.

Various attempts have been made to solve this problem. For example,hollow soles have been provided comprising outside release valves, butthe amount of air exchanged is small and therefore does not alloweffective aeration of the foot. A solution that has achieved substantialsuccess is the one that foresees coating the inside of a perforatedrubber sole with a microporous membrane, thus impermeable to water butpermeable to air and sweat in the form of water vapour. However, thissolution also has some drawbacks. First of all, it is a passive aerationsystem, since there is no device inside the shoe that promotes thecirculation of air. The exchange of air only occurs when the sole islifted from the ground. Moreover, after a few uses the micropores can beblocked by dust and dirt and therefore are no longer able to carry outtheir aeration function.

SUMMARY OF THE INVENTION

The problem forming the bases of the present invention is therefore thatof providing an aeration system for shoes that allows an effective andefficient exchange of air and vapour between inside and outside of theshoe.

Such a problem is solved by an aeration system and device for shoes asoutlined in the attached claims.

Further features and advantages of the present invention will be betterunderstood from the description of some exemplary embodiments, which isgiven below by way of non-limiting illustration.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 represents a plan and section view of the sole according to theinvention;

FIG. 2 represents a section view according to the direction II-II ofFIG. 1;

FIG. 3 represents a side section view of the sole for shoes according tothe invention;

FIG. 4 represents a perspective view of the aeration device according tothe invention;

FIG. 5 represents a perspective view of the core of the aeration deviceof FIG. 4;

FIG. 6 represents a plan view of the aeration device according to adifferent embodiment;

FIG. 7 represents a side section view of a shoe comprising the aerationsystem according to the invention;

FIG. 8 represents an exploded perspective view of a further embodimentof the present invention;

FIG. 9 represents a perspective view of a detail of the embodiment ofFIG. 8 in assembled condition;

FIG. 10 represents a perspective view of an insole according to afurther embodiment of the invention;

FIG. 11 represents a plan view from below of the insole of FIG. 10;

FIG. 12 represents a front side view of the insole of FIG. 11 accordingto the section XII-XII.

FIG. 13 is a planar view from below of a second embodiment of the insoleaccording to the invention;

FIG. 14 represents a top perspective view of a further embodiment of theinsole of the invention;

FIG. 15 represents an exploded perspective view of a differentembodiment of the aeration device of the invention;

FIG. 16 represents a perspective exploded view of a further embodimentof the aeration device of the invention;

FIG. 17 represents a perspective exploded view of yet another embodimentof the aeration device of the invention;

FIG. 18 represents a phantom side view of a further embodiment of theaeration device of the invention;

FIG. 19 represents a side view of a different embodiment of the elasticcore of the invention;

FIG. 20 represents a bottom view of a further embodiment of the elasticcore of the invention;

FIG. 21 represents a phantom perspective view of an elastic coreaccording to the invention;

FIG. 22 represents a side view of the elastic core in FIG. 21.

FIG. 23 represents a phantom side view of a different version of theelastic core in FIG. 21;

FIG. 24 represents a bottom view of the elastic core in FIG. 23.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the figures, the aeration system being the object ofthe present invention shall now be described.

The aeration system of the invention comprises a hollow sole 1,typically but not exclusively a hollow sole made from rubber or anothersynthetic material. The sole may of course also be made from leather orcomprise a leather tread.

The hollow sole 1 comprises a first cavity 2, formed substantially atthe heel area, and a second cavity 3, positioned substantially at thesole of the foot and defined by an edge 1 a. Said cavities 2, 3 are openon top, i.e. at the inside of the shoe. The first cavity 2 and thesecond cavity 3 are in fluid communication through a channel 4 that isformed in the thickness of the sole and that continues, at the secondcavity 3, in a groove 5. To the right and left of the groove 5, aplurality of ramifications 6 project, in a substantially transversaldirection, which, similarly to the main groove 5, extend up to the edge1 a.

At the distal end of said main groove 5 and of said ramifications 6, theedge 1 a of the sole 1 comprises transversal holes 7, which place thecavity 3 in fluid communication with the outside. At the mouth of theholes 7 towards the outside valve means 8 are arranged. The valve means8 typically consist of a one-way valve for shoes. This type of valve isconventional and substantially consists of a small cylinder inside whicha flap is placed that only opens if the air flow is towards the outside,whilst it does not allow the entry of air from the outside. Said valvemeans 8 may also simply consist of a dividing wall or membrane made frommicroporous material (for example, GORETEX®), which allows air and waterto pass, but is waterproof.

An aeration device is housed in the sole 1 according to the invention.Such an aeration device preferably comprises pumping means 9, typicallya bellows pump, housed in the first cavity 2 of the sole 1. Such pumpingmeans 9 comprise a shell 10, formed from two half-shells 10 a, 10 b, anda distribution nozzle 11. The opening of the nozzle 11 is placed at thechannel 4. Said shell 10 is made from a plastic material that ensures acertain degree of flexibility. Preferably, the shell 10 shall have aShore A hardness of over 80, more preferably equal to or greater than90. In a preferred version, the shell 10 shall be made frompolyurethane, such as an adipate ester polyurethane having the Shore Ahardnesses outlined above.

The shell 10 houses an elastic core 12 therein. The main function ofsuch an elastic core 12 is to increase resistance to stepping and to actas a “shock absorber”. Indeed, it has been seen that the provision of ahollow pump without inner core at the heel leads to excessive yieldingof the footbed at that point and consequently causes an irregular andnot very comfortable gait. Moreover, if the hollow pump collapses, it isno longer able to recover its initial shape and the pumping function isthus ended.

The elastic core 12 can consist of conventional elastic means, like aspring. However, in the preferred embodiment shown in the drawings, suchan elastic core comprises an elastic insert made from an elastomer, likefor example polyethylene. Preferably, such an elastomer shall have aShore D hardness of over 60, more preferably over 80, even morepreferably over 90. In another preferred embodiment, the elastomer usedfor the elastic core 12 shall have a Shore A hardness of between 15 and30, more preferably about 20.

In order to avoid the elastic core 12 filling the entire volume insidethe shell 10, drastically reducing the volume of air pumped, such anelastic core 12 is of a size, in particular a thickness, such as tocreate a gap between the core and the inner walls of the shell 10. Inpractice, the shape of the elastic insert substantially follows that ofthe shell 10, but it has smaller dimensions so as to create the gapdescribed above. More preferably, the length and width of the elasticinsert will be about 50% the length and width of shell 10.

For the same purpose, according to the preferred embodiment shown inFIG. 5, the elastic core is perforated on three sides, so that a networkof small channels 13, 13′, 13″, 13′″, 13″″ is formed therein. In thisway, the elastic core 12 itself forms a bellows pump that is associatedin action with that of the shell 10.

According to a particularly preferred embodiment of the invention, theelastic core 12 and/or the shell 10 shall contain perfume. Typically, a“compound” of the rubber/plastic material shall be made with theperfume, which shall thus be absorbed in the material and shall bereleased very gradually. Alternatively, the perfume can be contained inmicrospheres arranged inside and/or outside the elastic core 12 or onthe surface of the shell 10, so as to have an even longer-lastingrelease, mediated by the mechanical action (rubbing) and not just by thenormal evaporation of the perfume.

The shell 10 preferably has substantially flat base surfaces 14, 14′ anda side surface 15 that has sides with concave profile joined by roundedcorners. This shape allows the side surface 15 to be stiffened, keepinga good flexibility of the base surfaces 14, 14′. In this way the bellowspump can easily carry out its pumping action without collapsing, noteven partially, under the weight of the heel. In another preferredversion, shown in FIGS. 8 and 9, the shell 110 has the long sides with arectilinear profile and the end portions rounded.

By way of example, the shell 10 can have the following size: about 6 cmlength, about 4 cm width, about 2 cm thickness. In this case, it hasbeen determined that the inventive device allows the recirculation ofabout 15-17 cc air/vapour within the shoe. Such a volume shall decreaseaccording to the bulk of the elastic core 12 arranged inside the shell10, but it shall in any case be between 5 and 10 cc.

It is understood that it may be possible to vary the dimensions of theshell 10 according to requirements, for example according to the type ofshoe or the size.

As shown in FIG. 6, one or both of the base surfaces 14, 14′ maycomprise a pumping button 16 formed integrally in the thickness of theshell 10 by shaping a substantially C-shaped or horseshoe-shaped blindgroove 17 on the base surface. In this way, the base surface 14, 14′ isstrengthened, since the groove 17 acts as a reinforcing rib, without forthis reason losing pumping capacity.

As shown in FIG. 3, according to a preferred embodiment of the inventionthe second cavity 3 houses a pad 18. Such a pad 18, which has thefunction of supporting the sole of the foot increasing the comfort ofwalking, can preferably be made from an expanded synthetic material withopen cells, like latex foam or polyester-based expanded polyurethane.Alternatively, the pad 18 can be made from a needled material, like aneedled non-woven fabric, preferably with continuous needled thread, aneedled felt or a needled synthetic material (PE or PP). Alternatively,the pad 18 shall be made from an elastomer in which holes or microholesshall be made to make it porous. With the described materials, the pad18 shall be permeable to air/vapour and shall contribute to the pumpeffect created by the pumping means 9 arranged at the heel.

In another embodiment, shown in FIG. 8, the pad 118 shall be made fromrubber or another elastomer and shall comprise a perforated top surface130 and a bottom surface from which a plurality of flexible flaps 131project. The flaps 131 may be arranged perpendicular to the bottomsurface of the pad 118 or else in an inclined position and may havevarious shapes, for example with rectilinear or curved profile, etc. Thefunction of the pad 118 is totally similar to the one described abovefor the pad 18, however the structure with flaps 131 allows a possibleblockage of the groove 5 and/or of the ramifications 6 to be avoidedwhen walking.

The shape of the pad 18, 118 shall basically follow the shape of thecavity 3 in which it is housed, but it shall preferably have slightlysmaller dimensions, so as to create a gap along the perimeter of thecavity.

In a particularly preferred embodiment of the invention, the pad 18, 118shall contain a perfume. The same technologies, per se known, describedabove may be used for the elastic core 12 and for the shell 10 of thepumping means 9.

FIG. 7 shows the section of a shoe 19 that comprises the sole 1according to the invention and a vamp 21. The vamp 21 can be made fromany material normally used for shoes, even from a waterproof material.

As usual a footbed 20 is fixed on the sole 1, at the side facing towardsthe inside of the shoe. Such a footbed 20 shall preferably be aperforated footbed, so as to promote the passage of air/vapour. In anycase, it must be a breathable footbed. It is also important that thefootbed 20, if coupled with the sole by gluing, be fixed just along theedges, to avoid the layer of glue compromising the breathability of thefootbed 20.

If desired, this footbed 20 may also comprise a perfume, as describedabove, or a sanitising, antibacterial substance, etc. The technology ofthe microspheres may be particularly preferred in this case.

In the preferred embodiment of FIG. 7, the vamp comprises a breathablelayer 22 of air/vapour-permeable material therein. Such a material cangenerally be one of the materials described above for the pad 18 and canpossibly contain a perfume or a sanitising or antibacterial substance.

The inner side of said breathable layer 22 may, in turn, be coated witha thin layer of skin or another finishing material for shoes.

FIGS. 8 and 9 show a different embodiment of the sole 1 of theinvention. The sole comprises a base body 101 on which an insole 132 ishoused. The insole 132 is arranged on an impression 133 formed on thetop surface of the base body 101 and having a shape matching that of thebottom surface of the insole 132.

In turn, the insole 132 comprises a first cavity 102, arranged at thearea of the heel, and a second cavity 103, arranged at the area of thesole of the foot, such cavities being totally similar to the cavities 2,3 described for the embodiment of FIG. 1. A channel 104 joins the firstcavity 102 with the second cavity 103. A second channel 134 places thesecond cavity 103 in communication with the outer edge of the insole 132and therefore, through the corresponding hole 135 a arranged on the sidesurface of the base body 101, with the outside. A further channel 136,together with the hole 135 b arranged on the side surface of the basebody 101, in the heel area, places the first cavity 102 in communicationwith the outside.

The sole 1 also in this case comprises an aeration device. Such anaeration device, as described above, preferably comprises pumping means109, typically a bellows pump, housed in the first cavity 102 of theinsole 132. The pumping means 109 comprise a shell 110, also formed fromtwo half-shells as described previously, in which an elastic core 112totally similar to the one described previously is housed. The elasticcore 112 shall therefore also have a plurality of channels 113, 113′,113″, 113′″, 113″″ formed therein. The shape of the shell 110 and,correspondingly, of the elastic core 112 is as stated different to thatof the shell 10 and of the elastic core 12 described previously, but thelatter may be used irrespectively.

The shell 110 also comprises two nozzles 111 a, 111 b arranged at thetwo ends, intended to align with the channels 104, 136 that place thefirst cavity 102 in communication with the second cavity 103 and withthe outside, respectively. The shell 110, on the joining line of the twohalf-shells, also has a projecting edge 137, intended to rest on a step138 formed along the side walls of the first cavity 102.

In a particular embodiment, at the nozzles 111 a, 111 b and therefore atthe hole 135 b and the channel 104, respectively, valve means 108 a, 108b shall be arranged, preferably consisting of a one-way valve asdescribed above. The valve means 108 a can allow just the entry of airfrom the outside, whereas the valve means 108 b shall allow the airsucked in to be sent to the second cavity 103 and from here, through theholes of the pad 118, inside the shoe. This solution shall beparticularly useful in hot weather conditions, since it allows fresh airto be introduced inside the shoe, avoiding overheating of the foot andthus increasing the feeling of comfort. Alternatively, preferably incold weather conditions, the valve 108 a shall just allow foul air to beejected to the outside from inside the shoe, whereas the inner valve 108b shall allow the foul air to be sucked in from the cavity 103 andtherefore from inside the shoe. In this way a forced circulation of airaround the foot will be always obtained, without however injecting coldair that would cause excessive cooling of the foot. This solution, whichwe can define “winter system” in contrast with the so-called “summersystem” described above, may be obtained by simply mounting the valvemeans 108 a, 108 b in inverted position or even more simply by invertingthe positioning of the pumping means 109.

In this embodiment, unidirectional valve means 108 c are also preferablyarranged at the channel 134 and the hole 135 a, which for example shallallow air to be sucked in from the outside in the “summer system” andfoul air to be ejected in the “winter system” described above.

It should be noted that the provision of the channel 134 and of the hole135 a, to place the second cavity 103 in communication with the outside,is not necessary and can therefore be omitted, so as to allow just theexchange of air between the second cavity 103 and the inside of theshoe.

Advantageously, a pad 18, 118 is housed in the second cavity 103 asdescribed previously.

A perforated footbed 20 can advantageously be arranged on the insole132.

FIGS. 10, 11 and 12 show a different embodiment of the presentinvention. The figures show an insole 232 to be inserted on a base body101 of a sole suitably arranged and carrying a matching impression ontop.

The insole 232 is integral and comprises a thickened rear portion 232 a,corresponding to the heel region, and a front portion 232 b carrying aplurality of through holes.

The rear portion 232 a comprises an opening 240 intended to house thepumping means 209, similar to those described above and thus consistingof a shell 210 in which an elastic core 212 is housed. The shell 210,formed from two half-shells, has a raised edge 237 and a nozzle 211 thatconstitutes the air inlet/ejection opening in the area where they meet.The raised edge 237 snap inserts into a suitable groove 241 formed alongthe side wall of the opening 240. The elasticity of the elastomericmaterial from which the insole 232 is made allows its deformation andtherefore the insertion or removal of the pumping means 209.

As shown in FIG. 12, the shell 210 projects on top and below from thethickness of the insole 232, so as to promote the pumping action whilewalking.

As shown in FIG. 11, the bottom surface of the insole 232 has aplurality of ridges 242 defining empty spaces that, overall, form an airchamber between the bottom surface of the insole 232 and the innersurface of the sole on which the insole rests. Again on the bottomsurface of the insole 232, at the area where the nozzle 211 of thepumping means 209 is arranged, two ribs 243 a, 243 b are arranged thatgo for a first portion substantially parallel and then diverge untilthey reach the edge of the insole. Such ribs 243 a, 243 b constitute achannel for the air sucked in/ejected through the hole 244 arranged onthe side edge of the insole 232. At such hole 244, the bottom surface ofthe insole 232 further comprises a seat 245 for valve means of the typedescribed above.

In an embodiment not shown, the shell 210 shall be similar to the shell110 and shall thus be equipped with two nozzles, the first nozzle 211facing towards the inside and the second nozzle at a channelcommunicating with the outside in the region of the heel. Unidirectionalvalve means shall preferably be positioned at the nozzles; thisembodiment is therefore similar to that which has been outlined abovefor the embodiment of FIG. 8 and shall not be described any further. Inthis case, the opening 244 and the relative unidirectional valve meanscan also be omitted.

The use of the insole 232 can also avoid the positioning of a footbed 20inside the shoe.

FIGS. 13 and 14 show further embodiments of an insole 332 or 423according to the invention.

The insole 332 has the function of a footbed and then replaces thelatter in a shoe. The insole 332 can be thus adapted to any shoe, whichwill not require to be arranged for receiving the insole. As will bebetter understood from the description below, the aeration devicecoupled to the insole 332 will not require any air intake or vent,either inwardly or outwardly, respectively, since it will cause an innerair circulation of a sufficient amount to promote the removal of sweat,while maintaining foot thermostatting.

Similarly to what has been described in relation with the insole in FIG.10, the insole 332 is integrally formed, and comprises a thickened rearportion 332 a, corresponding to the heel region, and a front portion 332b carrying a plurality of through holes.

The rear portion 332 a comprises an opening 340 intended to housepumping means similar to those described above and thus consisting of ashell with an elastic core being housed therein.

A preferred embodiment of pumping means 309 suitable for the insole 332is shown in FIG. 15. The shell, formed by two half-shells 310 a, 310 bhas, in the area where they meet, a raised edge 337 and a nozzle 311which is the air inlet/ejection port. The raised edge 337 snap insertswithin a suitable groove 341 that is formed along the side wall ofopening 340. The elasticity of the elastomeric material from which theinsole 332 is made allows the latter to be deformed, and thus theinsertion or removal of the pumping means 309. The shell 310 projects ontop and below from the thickness of the insole 332, so as to promote thepumping action while walking.

An elastic core 312 is housed within the shell, which in this embodimentis elongated cap-shaped, the support edge 350 thereof being interruptedby a series of notches 351. The notches 351 have the function ofpromoting the displacement of the material when the core is pressed, andthe subsequent elastic return thereof. In a preferred embodiment, thenotches 351 will have a greater depth at the bent ends of the core 312,and a lower depth at the long sides, such as to give more resistance andelastic return to the core 312.

Preferably, the elastic core 312 is made of a SBS elastomer(Stirene-Butadiene-Stirene) admixed with stirene polymers or of a SEBSelastomer (Stirene-Ethylene-Butylene-Stirene) admixed with polyolefinssuch as polypropylene (PP), polyethylene (PE) or ethylene vinyl acetate(EVA) or of the same polyurethane material as described above withrespect to the shell. Preferably, these elastomer compounds have a ShoreA hardness (after 3 seconds) ranging between 40 and 70, more preferablybetween 40 and 65 (ISO 868).

A suction/delivery cannula 352 for the air is associated with the nozzle311.

As shown in FIG. 13, the lower surface of insole 332 is run through by alongitudinal channel 353 that starts from the opening 340, at the areain which the pumping means nozzle 311 is positioned, and runs to the tipof insole 332. In the first length, the channel 353 acts as a seat forthe cannula 352 of the pumping means 309, whereas in the second length,at the foot sole area, it opens into a plurality of branches 354, whichare substantially fish-bone arranged and accommodate the through holes355 that communicate with the upper surface of insole 332.

FIG. 14 shows a different embodiment of an insole 432 according to theinvention, which is also designed to be universally used, like insole332, with those shoes that are not arranged to receive an aerationsystem.

In this case, unlike the insole 332, the pumping means 309 will bereceived by the upper surface of insole 432. To the purpose, the uppersurface 432′ will comprise, in the heel area (which is thickened to thepurpose) a seat 440 for the pumping means 309. The seat 440 is blind,such as to have a bottom surface that acts as a support for the pumpingmeans, and comprises, along the side surface thereof, a groove 441 forsnap-engagement with the raised edge 337 of shell 310. From the seat 440there starts a longitudinal channel 453, which is intended toaccommodate the cannula 352 of the pumping means 309. The channel 453opens into a recessed chamber 456 in which a pad 18, 118 can be housed,as set forth above.

Both the insole 332 in FIG. 13 and the insole 432 in FIG. 14 maycomprise, on the upper surface thereof that is intended to come incontact with the foot, a finishing layer of fabric, leather or othersuitable material, duly drilled in order to allow the air to passtherethrough.

In a particularly preferred embodiment of the invention, the insole 332,432 and the pumping means thereof are integrally made, such that theraised edge 337 of the latter results to be drowned in the insolematerial.

FIG. 16 shows a different embodiment of the pumping means according tothe invention. In this embodiment, the shell comprises two half-shells410 a, 410 b which are totally similar to those described above, exceptfor two nozzles 411 a, 411 b being arranged along the raised edge 437 ina diametrally opposite position. One-way valves 453′, 453″ of the typedescribed above are associated with the nozzles 411 a, 411 b. The frontvalve 453′, associated with the nozzle 411 a in which the cannula 352 isinserted, will be generally mounted such as to allow the air to bedelivered by the pumping means 409 to the foot sole, while the rearvalve 453″ will be mounted in the opposite direction, such as to allowonly the suction of air from the heel area. The embodiment in FIG. 16has been specifically designed for summer use, or however in hotclimates. In fact, the external air is sucked from the outside throughthe slit provided between the heel and shoe instep and is thus fed intothe shoe, thus aerating the latter. Under cold climate conditions, thiswould lead to an excessive cooling of the foot. On the contrary, theembodiment in FIG. 15 allows the circulation of the same air beingwithin the shoe, thus obtaining a good thermostatting, while causing aturbulence suitable to keep the foot dry.

FIG. 17 shows a further embodiment of the aeration device of theinvention. The pumping means 509 comprise two half-shells 510 a, 510 bhaving a raised edge 537, a nozzle 511, with which a cannula 352 can beassociated, and elastic means 512 consisting of a spring. Of course, theversion similar to that in FIG. 16 can be also provided, i.e. the summerversion with two nozzles provided with unidirectional valves. The inwardface of half-shells 510 a, 510 b has holding ridges 560, 560′ intendedto act as a stop for both ends of the spring.

The elastic means 512 preferably consist of a helical spring developingsubstantially in a truncated-cone shape with elongated annular profile.

According to a particularly preferred embodiment, as shown in FIG. 21,the elastic means consist of a flexural spring 912 consisting of anelongated annular base 975 and a treading plate 976, which are joined toeach other by means of pantograph-shaped bending elements 977, 977′. Thebending elements 977, 977′ are >-shaped and <-shaped, respectively, andconsist of a lower arm 977 a, 977 a′ and an upper arm 977 b, 977 b′. Thebending elements 977, 977′ are arranged in an inversed position, i.e.the first bending element 977 originates from a first rectilinear side978 of the base 975, at a first end of base 975, and develops like >until it is connected to a first end of the treading plate 976; on thecontrary, the second bending element 977′ originates from a second side978′ of base 975, at a second end of base 975 opposite to said firstend, and develops like < until it is connected proximate to a second endof the treading plate 976.

The treading plate 976 comprises, along both rectilinear sides,rectangular notches having a complementary shape to that of the upperarms 977 b, 977 b′ of the bending elements 977, 977′, of which thefunction is to allow the complete bending of the upper arms 977 b, 977b′. For the same reason, the respective lower arms 977 a, 977 a′ arelaterally fastened relative to the rectilinear sides 978, 978′ of base975, such as to avoid interfering therewith during bending.

Preferably, the flexural spring 912 is made of polymeric material. Morepreferably, said polymeric material will have a bending resistanceranging between 850 and 1100 Kgf/cm² (ASTM D790) and a bending modulusranging between 24000 and 28000 Kgf/cm² (ASTM D790). Most preferably,the polymeric material will be an acetal polyoxymethylene copolymerhaving about 950 Kgf/cm² bending resistance and about 26000 Kgf/cm²bending modulus.

In FIG. 22 is shown a different embodiment of the flexural spring 912,in which, below the treading plate 976 is provided an elastic cylinder1000. The elastic cylinder 1000 is hollow, such as to form a tubularstructure and is made of an elastomer, such as polyethylene. Preferably,such an elastomer shall have a Shore D hardness of over 60, morepreferably over 80, even more preferably over 90. In another preferredembodiment, the elastomer used for the elastic cylinder 1000 shall havea Shore A hardness of between 15 and 30, more preferably about 20.

The upper end of the elastic cylinder 1000 is housed in a suitableannular seat 999 formed on the lower face of the treading plate 976,such as to be held therein. To the purpose, the elastic cylinder 1000can advantageously be fixed, for example, by gluing to the annular seat999.

The function of the elastic cylinder 1000 is both of allowing a betterelastic return of the spring 912 even after long treading cycles, andincreasing the comfort of walking.

FIG. 18 shows a different embodiment of a shell 609 in which the elasticcore 312 can be seen. As in the above versions, the shell consists oftwo half-shells 610 a, 610 b that are coupled to form a raised edge 637along which a nozzle 611 is placed (the summer version with two nozzlesand the unidirectional valves can be provided also in this case). Inthis embodiment, however, the upper half-shell 610 a has a convexportion 670 a, and a flat portion 670 b. The convex portion is intendedto protrude on top of the insole 332, 432, thereby being an operatingpush-button for the pumping means 609. This embodiment is conceived fora women or child shoe, wherein the heel portion is less extended andthus requires, also for walking comfort purposes, a small-sizedoperating push-button for the pump. The version in FIG. 18 has thepurpose of reducing the size of the operating push-button, withoutsubstantially reducing the volume of pumped air, and thus the efficacyof the pumping means 609.

FIG. 19 shows, on the other hand, a different embodiment of the elasticcore 712 according to the invention. Also in this case, the elastic core712 is elongated cap-shaped, but instead of the notches, it has aplurality of holes 780 in the vicinity of the contour thereof, such asto create as many air vents when the pumping means are being pressed.The elastic core 712 can be advantageously made of the same materials asdescribed above for the embodiment in FIG. 15.

FIG. 20 is a bottom view of an elongated cap-shaped elastic core 812entirely similar to the variant in FIG. 15, though comprising, on thelower surface thereof, a series of reinforcement ribs 890. It mayhappen, indeed, that the elastic core tends to lose its elastic returnfeature due to continued treading. This drawback can be overcome, eitherby increasing the thickness of the piece (which is normally 1-2 mm),with the risk of stiffening it too much, or introducing the ribs 890.

In all the variants shown above, the shell 10, 110, 210, 310, 410, 510,610 has a height ranging between 8 and 20 mm, preferably between 10 and14 mm, most preferably about 12 mm and is however structured such as toproject above the insole plane by 3-6 mm. This can be obtained either byproviding the two half-shells symmetrically shaped, i.e. having the sameheight (for example, 6 mm the lower half-shell and 6 mm the upperhalf-shell) or by coupling a higher half-shell with a less projectingone (for example, 8 mm and 12 mm, respectively).

In a particularly preferred embodiment of the present invention, thefootbed 20 and/or the vamp 21 and/or the insole 332, 432 shall comprisea phase-change material. Phase-change materials, known with the acronymPCM, are materials able to pass from solid state to liquid state andvice-versa when a particular temperature is reached that falls withinthe range of weather conditions of common use, in particular for an itemof clothing. Such weather conditions, in the case of a shoe, correspondto a temperature in the order of 25°-30° C. PCMs exploit the physicalprinciple that when a material changes its physical state, it maintainsthe temperature equivalent to its melting point until all of thematerial has changed state. If the material melts after the climatictemperature has risen, it absorbs heat, vice-versa if it solidifiesfollowing cooling, it releases heat and by doing so maintains itstemperature constant. It is thus clear that by inserting a PCM in ashoe, it shall take care of avoiding overheating or cooling of the foot,absorbing the excess heat from inside the shoe or releasing heat in thecase of external cooling.

PCMs used for the purpose of the present invention consist of mixturesof paraffins having different melting points and high heat of fusion,encapsulated in microcapsules that are used to coat a substrate or to beincluded in said substrate. In particular, the material used is known asOutlast Thermocules. Preferably, the PCM shall be present at least onthe face of the footbed 20 and/or of the vamp 21 facing towards thefoot.

The use of a PCM in the present invention is of particular value.Indeed, the active air circulation system described above has thelimitation of only providing efficient ventilation during walking,whereas in still conditions it is reduced to a passive system. In theseconditions a heating or cooling of the foot could therefore occur,according to the weather conditions. The phase-change material thustakes care of keeping the temperature of the foot constant when notmoving. On the other hand, the use of just PCM, without the activeventilation system, would not be sufficient: as stated above, theability of the PCM to keep the temperature constant runs out when all ofthe material has changed phase, and therefore lasts a limited amount oftime. In the present case, when walking once again, the activeventilation system of the invention takes care of thermostatting theshoe and regenerating the PCM, i.e. heating the inside of the shoe incold weather and cooling it down in hot weather. It goes without sayingthat with the alternation of stopping and moving, typical of normaldaily use of the shoe, the system of the present invention allowsperfect thermostatting.

The aeration system of the invention works in the following way.

The inside of the shoe is in fluid communication, through the perforatedfootbed 20, with the cavities 2, 102 or opening 209 and cavities 3, 103of the sole and therefore, through the holes 7, 135 a, 135 b, 244 andthe valve means 8, 108 a, 108 c, 245, with the outside. In theembodiment of FIG. 7, a further way of communication with the outsideconsists of the breathable layer 22 that allows air to enter/exit fromthe instep of the shoe, as shown by the arrows.

In practice, in each step the first thing to be placed down is the heel,therefore the pumping means 9, 109, 209 are compressed causing a flow ofair/vapour from the first cavity 2, 102 or opening 209 to the secondcavity 3, 103 and then towards the outside. Then the sole of the foot isplaced down, with relative compression of the pad 18, 118 and furtherpushing of air/vapour towards the outside. When the heel (first) and thesole of the foot (after) are raised, the aeration device—pumping means9, 109, 209 and pad 18, 118—causes a sucking of air/vapour from insidethe shoe 19, through the holes of the footbed 20, as schematised by thearrows. A continuous and consistent air circulation is thus created,which has the effect of taking away sweat, keeping the foot dry, and ofthermostatting the inside of the shoe, avoiding overheating of the footabove all in hotter weather and/or during physical effort.

In the embodiment of FIGS. 8 and 9, the presence of the unidirectionalvalves 108 a, 108 b, as explained above, according to weatherconditions, allows air to be taken in just from the outside and thecirculation of such air inside the shoe; or else, in cold weather, theair present in the shoe to be ejected to the outside without substantialintake from the outside.

The insoles 332, 423 shown in FIGS. 13 and 14, as stated above, areuniversal, i.e. they can be inserted in place of the footbed in anyshoe, without requiring any pre-arrangement. Therefore, the individualair-exchange point with the external environment is the shoe neck. Theoperation of the device is, however, completely similar to thatdescribed above.

The advantages of the aeration system of the invention are clear and inpart have already been highlighted in the description above.

The aeration system of the invention, in practice, constitutes an activeand not passive system. Indeed, the air/vapour is not simply ventedthrough aeration holes, as in many solutions of the prior art, but asort of forced circulation is created that substantially increases theefficiency of aeration.

The aeration device—pumping means 9, 109, 209 and pad 18, 118—acts as alung, taking in and letting out air/vapour in each step, thus the volumeof circulated fluid is high.

As well as the effect of keeping the foot dry and thermostatted, thepreferred provision of perfume in a slow-release form allows the problemof bad smells to be solved for a long if not indefinite time.

The combination of the active ventilation system of the invention and aphase-change material (PCM) allows the advantages of the invention tolast longer even when not walking.

The aeration device, i.e. the pumping means 9, 109, 209 and the pad 18,118, also acts as a shock absorber, above all thanks to the provision ofthe elastic core 12, 112, 212 inside the pumping means 9, 109, 209. Inthis way, the pumping effect is also associated with considerablecomfort when walking, which allows the use of the aeration system of theinvention also for sports and technical shoes.

In particular, the aeration system of the invention may be used both innormal shoes and in tennis and/or athletics shoes, in hiking and walkingshoes in general or in work shoes and anti-industrial accident shoes.

It is understood that only some particular embodiments of the aerationsystem for shoes object of the present invention have been described, towhich the man skilled in the art shall be able to bring anymodifications required to adapt it to particular applications, withouthowever departing from the scope of protection of the present invention.

It shall, for example, be possible to provide that the footbed 20 beremovable, so as to allow access to the bellows pump 9 or to the pad 18to replace them or impregnate them with more perfume.

1. An aeration system for shoes, comprising a hollow sole having anaeration device in fluid communication both with the inside of the shoeand with the outside, at least one first cavity or opening being formedinside said hollow sole, pumping means being housed in said at least onefirst cavity or opening, characterised in that said pumping meanscomprise a shell and one or more distribution nozzles, a flexible corebeing housed inside said shell.
 2. The aeration system for shoesaccording to claim 1, in which said elastic core comprises an elasticinsert made from an elastomer.
 3. The aeration system for shoesaccording to claim 2, in which said elastomer has a Shore D hardness ofover 60, preferably over 80, most preferably over
 90. 4. The aerationsystem for shoes according to claim 2, in which said elastomer has aShore A hardness of between 15 and 30, preferably about
 20. 5. Theaeration system for shoes according to claim 2, in which the shape ofsaid elastic insert substantially follows that of the shell in which itis housed, but it has smaller dimensions so as to create a gap betweenthe core and the inner walls of said shell.
 6. The aeration system forshoes according to claim 2, in which said elastic insert is perforatedon three sides, so that a network of small channels is formed therein.7. The aeration system for shoes according to claim 1, wherein saidelastic core has an elongated cap shape and is made of a SBS elastomer(Stirene-Butadiene-Stirene) admixed with stirene polymers or of a SEBSelastomer (Stirene-Ethylene-Butylene-Stirene) admixed with polyolefinssuch as polypropylene (PP), polyethylene (PE) or ethylene vinyl acetate(EVA), or of a polyurethane material such as an adipate esterpolyurethane.
 8. The aeration system for shoes according to claim 7,wherein said elastomeric compound has a Shore A hardness (after 3seconds) ranging between 40 and 70, or between 40 and 65 (ISO 868). 9.The aeration system for shoes according to claim 7, wherein said elasticcore comprises a support edge interrupted by a series of notches. 10.The aeration system for shoes according to claim 9, wherein said notcheshave a greater depth at the bent ends of the elastic core and a lowerdepth at the long sides.
 11. The aeration system for shoes according toclaim 7, wherein said elastic core comprises a plurality of holes at thecontour thereof.
 12. The aeration system for shoes according to claim 7,wherein the lower face of the elastic core has a series of reinforcementribs.
 13. The aeration system for shoes according to claim 1, whereinsaid shell consist of two half-shells that are coupled to form a raisededge along which at least one nozzle is placed, the upper half-shellhaving a convex portion and a flat portion, wherein said convex portionis intended to project on top to form an operation push-button for thepumping means.
 14. The aeration system for shoes according to claim 1,in which said elastic core is a spring.
 15. The aeration system forshoes according to claim 14, wherein said spring is a helical springhaving a truncated-cone development and an elongated annular profile.16. The aeration system for shoes according to claim 14, wherein saidspring is a flexural spring.
 17. The aeration system for shoes accordingto claim 16, wherein said flexural spring consist of an elongatedannular base and a treading plate, which are joined by pantograph-shapedbending elements.
 18. The aeration system according to claim 17, whereinsaid bending elements are >-shaped and <-shaped, respectively, andconsist of a lower arm and an upper arm.
 19. The aeration systemaccording to claim 18, wherein said bending elements are arranged sothat the first bending element originates from a first rectilinear sideof the base, proximate to a first end of base, and develops like > untilit is connected to a first end of the treading plate; the second bendingelement originates from a second rectilinear side of base, at a secondend of base opposite to said first end, and develops like < until it isconnected proximate to a second end of the treading plate.
 20. Theaeration system according to claim 17, wherein said treading platecomprises, along both the rectilinear sides, rectangular notches havinga complementary shape relative to that of upper arms of the bendingelements and wherein the respective lower arms are laterally fastenedrelative to the rectilinear sides of base, such as to avoid interferingtherewith while bending.
 21. The aeration system for shoes according toclaim 17, wherein an elastic cylinder is placed below said treadingplate.
 22. The aeration system for shoes according to claim 21, whereinsaid elastic cylinder is hollow such as to form a tubular structure andis made of an elastomer preferably having a Shore D hardness higher than60, or higher than 80, or higher than 90; or the elastomer will have aShore A hardness ranging between 15 and 30, preferably about
 20. 23. Theaeration system for shoes according to claim 22, wherein said elastomeris polyethylene.
 24. The aeration system for shoes according to claim22, wherein the upper end of the elastic cylinder is housed within thesuitable annular seat formed on the lower face of the treading plate andis preferably fixed by gluing.
 25. The aeration system for shoesaccording to claim 14, wherein said spring is made of polymericmaterial.
 26. The aeration system for shoes according to claim 25,wherein said polymeric material has a bending resistance ranging between850 and 1100 Kgf/cm² (ASTM D790) and a bending modulus ranging between24000 and 28000 Kgf/cm² (ASTM D790).
 27. The aeration system for shoesaccording to claim 25, wherein the polymeric material is an acetalpolyoxymethylene copolymer having about 950 Kgf/cm bending resistanceand about 26000 Kgf/cm² bending modulus.
 28. The aeration system forshoes according to claim 14, said spring being contained within a shellconsisting of two half-shells, the inner surface of said half-shellscomprising holding ridges intended to act as a stop for both ends of thespring.
 29. The aeration system for shoes according to claim 1, whereina cannula for the suction/delivery of air is associated with a nozzle ofsaid shell.
 30. The aeration system for shoes according to claim 2,wherein said elastic core and/or said shell contain a perfume.
 31. Theaeration system for shoes according to claim 30, in which said perfumeis absorbed in the material of the elastic core and/or of the shell oris associated with it in the form of microspheres.
 32. The aerationsystem for shoes according to claim 1, in which said pumping means are abellows pump.
 33. The aeration system for shoes according to claim 1, inwhich said hollow sole comprises at least one second cavity, positionedsubstantially at the sole of the foot and defined by an edge, said atleast one second cavity being in fluid communication with said at leastone first cavity through a channel.
 34. The aeration system for shoesaccording to claim 33, in which said channel continues, at said at leastone second cavity, in a groove, with a plurality of ramificationsprojecting to the right and left of said groove, in a substantiallytransversal direction, said main groove and said ramifications extendingup to said edge.
 35. The aeration system for shoes according to claim34, in which, at the distal end of said main groove and of saidramifications, the edge of the hollow sole comprises transversal holes,which place said at least one cavity in fluid communication with theoutside.
 36. The aeration system for shoes according to claim 35,wherein valve means are arranged at the mouth of said holes towards theoutside.
 37. The aeration system for shoes according to claim 33, inwhich said at least one second cavity houses a pad.
 38. The aerationsystem for shoes according to claim 37, in which said pad is made froman expanded synthetic material with open cells, like latex foam orpolyester-based expanded polyurethane, or else a needled material, likea needled non-woven fabric, preferably with continuous needled thread, aneedled felt or a needled synthetic material (PE or PP), or else from aperforated or microperforated elastomer.
 39. The aeration system forshoes according to claim 37, in which said pad comprises a perfume. 40.The aeration system for shoes according to claim 1, wherein said hollowsole comprises a base body and an insole, said base body comprising animpression of a shape matching the shape of the bottom surface of theinsole and on which said insole is arranged.
 41. The aeration system forshoes according to claim 40, wherein said insole comprises a firstcavity, arranged at the area of the heel and in which said pumping meansare arranged, and a second cavity, arranged at the area of the sole ofthe foot, and in which a first channel joins said first cavity with saidsecond cavity; a second channel placing said second cavity incommunication with the outer edge of the insole and therefore, throughthe corresponding hole arranged on the side surface of the base body,with the outside.
 42. The aeration system for shoes according to claim41, wherein a third channel, together with the hole arranged on the sidesurface of the base body in the area of the heel, places said firstcavity in communication with the outside.
 43. The aeration systemaccording to claim 40, wherein said shell comprises two nozzles arrangedat the two ends, intended to be aligned with said channels that placesaid first cavity in communication with the second cavity and with theoutside, respectively.
 44. The aeration system for shoes according toclaim 43, wherein, at said nozzles and therefore at the hole and thefirst channel, respectively, first and second unidirectional valve meansshall be placed, mounted so that said first valve means allow just theentry of air from the outside, whereas said second valve means allow airto be sent from the outside to said second cavity and from here, throughthe holes of the pad, inside the shoe; or else said first and secondvalve means are mounted so as to allow an inverse air circulation. 45.The aeration system for shoes according to claims 41, wherein, at saidchannel and at the hole unidirectional valve means are arranged, saidvalve means being mounted so as to allow air to be taken in from theoutside; or else said valve means are mounted so as to allow air to beejected from the inside.
 46. The aeration system for shoes according toclaim 40, wherein said insole is integral and comprises a thickened rearportion, corresponding to the region of the heel, and a front portioncarrying a plurality of through holes.
 47. The aeration system for shoesaccording to claim 46, wherein said rear portion of said insolecomprises an opening intended to house said pumping means.
 48. Theaeration system for shoes according to claim 46, wherein the shell ofsaid pumping means has a raised perimetric edge and at least one nozzlethat constitutes the opening for taking in/ejecting air, said raisededge being able to be snap inserted in a groove formed along the sidewall of the opening.
 49. The aeration system for shoes according toclaim 40, wherein the bottom surface of the insole has a plurality ofridges defining empty spaces that, overall, form an air chamber betweenthe bottom surface of the insole and the inner surface of the base bodyon which the insole rests.
 50. The aeration system for shoes accordingto claim 46, wherein two ribs are arranged on the bottom surface of theinsole, at the area in which the nozzle of the pumping means isarranged, which extend for a first portion substantially parallel andthen diverge until they reach the edge of the insole, said ribsconstituting a channel for the air taken in/ejected through a holearranged on the side edge of the insole.
 51. The aeration system forshoes according to claim 46, wherein, at said hole, the bottom surfaceof the insole comprises a seat for unidirectional valve means.
 52. Theaeration system for shoes according to claim 1, wherein said shoecomprises said hollow sole as described in the previous claims and avamp, a breathable footbed being arranged on said hollow sole, at theside facing towards the inside of the shoe.
 53. The aeration system forshoes according to claim 52, wherein said footbed is perforated.
 54. Theaeration system for shoes according to claim 52, wherein said footbed iscoupled with said hollow sole by gluing just along the edges.
 55. Theaeration system for shoes according to claim 52, wherein said footbedcomprises a perfume, a sanitising or an antibacterial substance.
 56. Theaeration system for shoes according to claim 52, wherein said vampcomprises a breathable layer of air/vapour-permeable material therein.57. The aeration system for shoes according to claim 56, said breathablelayer being made from an expanded synthetic material with open cells,like latex foam or polyester-based expanded polyurethane, or else from aneedled material, like a needled non-woven fabric, preferably withcontinuous needled thread, a needled felt or a needled syntheticmaterial (PE or PP), or else from a perforated or microperforatedelastomer.
 58. The aeration system for shoes according to claim 56,wherein said breathable layer comprises a perfume, a sanitising or anantibacterial substance.
 59. The aeration system for shoes according toclaims 52, wherein said footbed is removable, so that to allow access tothe pumping means and/or to the pad for replacing them or forimpregnating them with the perfume.
 60. The aeration system for shoesaccording to claims 47, wherein the footbed and/or the vamp and/or theinsole comprise a phase changing material.
 61. The aeration system forshoes according to claim 60, wherein said phase-change materialcomprises mixtures of paraffins having different melting points and highheat of fusion, encapsulated in microcapsules.
 62. A shoe comprising anaeration system as outlined in claim
 17. 63. An aeration devicecomprising pumping means as described in claim
 17. 64. The aerationdevice according to claim 63, said device being a universal use insole.65. The aeration device according to claim 64, wherein said insolecomprises a rear thickened portion, corresponding to the heel region,and a front portion carrying a plurality of through holes, said rearportion comprising an opening intended to house said pumping means,wherein the lower surface of insole is run through by a longitudinalchannel starting from the opening, at the positioning area of the nozzleof the pumping means and develops proximate to the tip of insole, saidchannel, at the foot sole area, by opening into a plurality of branchesthat are substantially fish-bone arranged and house the through holescommunicating with the upper surface of insole.
 66. The aeration deviceaccording to claim 64, the upper surface of said insole comprising aseat in the heel area for said pumping means, the seat being blind, suchas to have a bottom surface, and comprising along the side surfacethereof a groove for snap-engagement with said pumping means, andwherein from the seat there starts a longitudinal channel that opensinto a recessed chamber that is suitable to house a pad.
 67. Theaeration device according to claim 64, wherein said insole and saidpumping means are integrally formed.
 68. The aeration device accordingto claim 63, wherein the upper surface of said insole comprises afinishing layer of fabric, leather or other suitable material.
 69. Aflexural spring consisting of an elongated annular base and a treadingplate, which are joined by bending elements, wherein said bendingelements are >-shaped and <-shaped, respectively, and consist of a lowerarm and an upper arm, and wherein said bending elements are arrangedsuch that the first bending element originates from a first rectilinearside of base, proximate to a first end of base, and develops like >until it is connected to a first end of the treading plate; the secondbending element originates from a second rectilinear side of base,proximate to a second end of base opposite said first end, and developslike < until it is connected to a second end of the treading plate;wherein said treading plate further comprises, along both rectilinearsides thereof, rectangular notches having a complementary shape relativeto that of upper arms of the bending elements, and wherein therespective lower arms are laterally fastened relative to the rectilinearsides of base, such as to avoid interfering with the latter whilebending.
 70. The flexural spring according to claim 69, wherein anelastic cylinder is placed below said treading plate, and wherein saidelastic cylinder is hollow such as to form a tubular structure and ismade of an elastomer preferably having a Shore D hardness higher than60, or higher than 80, or higher than 90; or the elastomer will have aShore A hardness ranging between 15 and 30, preferably about
 20. 71. Theflexural spring according to claim 70, wherein the upper end of theelastic cylinder is housed in a suitable annular seat formed on thelower face of the treading plate and is preferably fixed by gluing.